Strong magnetic frustration in Y3Cu9(OH)19Cl8: a distorted kagome antiferromagnet. Issue 10 (23rd February 2017)

• Record Type: Journal Article
• Authors: Puphal, Pascal; Bolte, Michael; Sheptyakov, Denis; Pustogow, Andrej; Kliemt, Kristin; Dressel, Martin; Baenitz, Michael; Krellner, Cornelius
• Is Part Of: Journal of materials chemistry. Volume 5:Issue 10(2017)
• Page Start: 2629
• Page End: 2635
• Publication Date: 2017-02-23
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c6tc05110c
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : A strongly frustrated ordered state can be induced in Y3 Cu9 (OH)19 Cl8 by slightly modifying the perfect kagome lattice YCu3 (OH)6 Cl3 . Abstract : We present the crystal structure and magnetic properties of Y3 Cu9 (OH)19 Cl8, a stoichiometric frustrated quantum spin system with slightly distorted kagome layers. Single crystals of Y3 Cu9 (OH)19 Cl8 were grown under hydrothermal conditions. The structure was determined from single crystal X-ray diffraction and confirmed by neutron powder diffraction. The observed structure reveals two different Cu-positions leading to a slightly distorted kagome layer in contrast to the closely related YCu3 (OH)6 Cl3 . Curie–Weiss behavior at high-temperatures with a Weiss-temperature θ W of the order of −100 K, shows a large dominant antiferromagnetic coupling within the kagome planes. Specific-heat and magnetization measurements on single crystals reveal an antiferromagnetic transition at T N = 2.2 K indicating a pronounced frustration parameter of θ W / T N ≈ 50. Optical transmission experiments on powder samples and single crystals confirm the structural findings. Specific-heat measurements on YCu3 (OH)6 Cl3 down to 0.4 K confirm the proposed quantum spin-liquid state of that system. Therefore, the two Y–Cu–OH–Cl compounds present a unique setting to investigate closely related structures with a spin-liquid state and a strongly frustrated AFM ordered state, by slightly releasing the frustration in a kagome lattice.